description abstract | The premovement time has been considered a critical factor of safety in building fire evacuations because the casualty of fire disasters is strongly associated with delayed evacuation. In the present study, an immersive virtual environment is employed to explore the effect of fire visibility, fire alarm voices, and individual characteristics (gender, occupation/major, and experience of fire safety training) on individuals’ fire evacuation premovement time in underground commercial buildings. A regression analysis of relevant time distribution is then provided. According to the results, the distribution of occupants’ premovement time varies in different underground commercial buildings. Overall fitting error is small in the Burr distribution and Weber distribution of a common regression model. Additionally, it proves that fire visibility exerts significant influence on occupants’ premovement time while other factors are not significantly influential in the case of predictable fire. Excluding their experience of fire prevention and safety training, factors such as fire alarm content, individual’s gender, and occupation (major) have a significant effect on premovement time when fires are not predictable. Moreover, the obtained findings could contribute to improving the current evaluation procedures of underground commercial building evacuation and relevant policies of fire prevention and safety. | |